Wireless systems are susceptible in many respects. These susceptibilities are increasing as new wireless technologies are growing in prevalence. Ad-hoc networks, where individual users communicate with each other directly without using intermediary network nodes, creates new susceptibilities to the users and networks. These susceptibilities can be categorized as “trust”, “rights”, “identity”, “privacy” and “security” related issues.
“Trust” refers to the assurance that information communicated in these systems can be shared. To illustrate, a wireless user may want to know that a communication was sent to it from a trusted source and using trusted communication nodes. The user in an ad-hoc network may have no knowledge that the communication was transferred over a hacker's wireless device with packet sniffing software. Additionally, with the use of tunneling, intermediate nodes transferring the communication may be transparent to the wireless user.
“Rights” (“rights management”) refers to the control of data. To illustrate, one wireless user may have limited rights in a wireless system. However, if that user colludes (knowingly or unknowingly) with a second node having superior rights, that user may gain rights above those that the user is allowed.
“Identity” refers to the control linked to the identity of the wireless user. To illustrate, a rogue wireless device may attempt to access a wireless network by pretending to be an authorized user of the network, by using that authorized user's identity. “Privacy” refers to maintaining privacy of the individual, data and context. A wireless user may not want others to know, which web sites he/she visits and, in particular, information sent to these sites, such as financial, medical, etc. “Security” refers to the security of the data and context, such as preventing an unauthorized individual access to a wireless user's information.
To reduce the susceptibility of wireless networks, techniques such as wired equivalent privacy (WEP), Wi-Fi Protected Access (WPA), Extensible authentication Protocol (EAP) and GSM based encryption are used. Although these techniques provide some protection, they are still susceptible to the trusts, rights, identity, privacy and security issued. To illustrate, although a particular wireless communication node may have the correct WEP keys to communicate with a wireless user, that user may not know whether he/she can “trust” that node.
Additionally, authentication of the user using these keys typically occurs at higher layers of the communication stack. Accordingly, even when these controls are in place, a rogue wireless user or hacker may have some (although limited) access to the communication stack. This access creates vulnerabilities, such as to denial of service attacks, among others.
Watermarks/signatures are techniques for adding metadata or unique information to media for signaling and/or security purposes. To reduce these susceptibilities to wireless communications, it is desirable to produce different tokens/keys for use in watermarks, signatures and encryption.